Serial section studies of surgical specimens removed for cancer by total or partial laryngectomy will be conducted with the objective of determining patterns of growth and spread within the larynx and outside this organ into adjacent structures. These studies provide the basis for determining the degree of invasion from the tumor's preoperative appearance on inspection, palpation, radiography and scanning studies. This type of knowledge allows the clinician to preserve the function of the larynx, pharynx and oral cavity when these structures must be removed for cancer in any particular case. The information is important, not only to the surgeon, but to the radiotherapist and the medical oncologist. Cancer of the floor of the mouth, tongue, mandible and maxilla is also being studied by this technique and should provide information of value to the clinician who treats diseases and who is concerned with the preservation of function to the greatest possible degree.